Goldsbtjby haedbn pond



GOLDSBURY HARDEN Pom), or ennns FALLS, new YORK.

. k t l PATENT OFFICE...

BLEACHING wooo PULP AND OTHER FiBRous MATE-RIA-LS.

* g I ---':-w- 4 SFECIPICA'IION fanning partial Lattersfiatent No. 32,1.452. dated J'u ly '1. 1885.

' I Application filed October 13,1881. (No specimens.)

new and useful Improvements "in the Process 'of Bleaching Wood Pulp, Textile Goods, and

other Fibrous Material by the use of Oxygen; and I do hereby declare that the-following is a full, clear, and exact description of the invention, which will enable others skilled in the art to which it appertains to makeand use the same. I, c,

The object of my invention is the process of bleaching wood pulp and any other material of a fibrous nature with oxygen in a quick, efficient, and economical manner; also to produce white pulp for the manufacture of paper from various fibrous substances, primarily wood pulp and other fibrous materialnot in use for that purpose owing to the inability of bleach ing it white on a commercial scale; also to reduce the cost of the process of bleaching wood pulp white.

All kinds of wood pulp and any other fibrous material can be bleached white expeditiously and economically Without materially injuring the most delicate fibers of the material of which these goods ar'ecomposed.

Heretofore bleaching has been done on a commercial scale principally with chlorine or some of the chlorides, although in some cases ozone has been applied to the science, and on some classes of goodssulphuric-acid gas is used. Neither the chlorine process nor any of thechlorides in the various ways they are used will bleach white wood pulp without many repetitions of the process and a partial destruction of the fiber. Wood fiber, excepting what is called chemical pulp, will not bleach whiter than a light yellow or cream color by any other known process without de- 7 composition taking place and an entire destruction of the fiber.

To carry my invention into effect, I use metallic'oxides with chlorine or any other. substance or solution that will yield oxygen by the action of these metallic oxides, depending entirely in this process upon the generation of oxygen in contact "with the material to be bleached, either inair or in abath of any sub stance which may be compatible with a bleachacti,on of the metallic oxides.

tank or the engine to its working capacity ing operation, and which is capable of yield ing up its oxygen through the agency of a metallic oxide. In this solution wood pul s and any other fibrous material to be bleached are thoroughly wet or mixed therein, thereby bringing'into a close and positive contact the material to be bleached and'the innumerable points of generation of the oxygen. To accomplish these results Iprepare a bath of weal; solution or mixture vot' any metallic oxide .mixed with water -such as the oxide of iron,

copper, zinc, lead, nickel, or,cobalt. I preferthe oxide of iron and zinc to all others. In using the oxides they are mixed with water, and are then thoroughly mixed with, the material being, bleached, ,so that the fibers thereof are completely covered with it, the me: tallic particles being deoxidized and oxidized to an unlimited extent, thereby developinga large quantity of oxygen.

In bleaching wood pulp and any other material of afibrous naturesuchas-hem'p, jute,

flax, cotton,-,or the waste of. any of these-for the manufactiire of paper I take the common bleaching tank or engine now ingeneral use p in paper-making, fill it partly full with water and with the metallicoxides mixed therein in the proportions of one pound of the oxide to one hundred pounds of the material to be bleached, this proportion being varied accordinglto the amount of oxygen required; then add a quantity of the solution of either chloride of lime or chlorine water, or any other solution capable of yielding oxygen by the with the ,wood pulp, heating with steam to nearly a boiling point. The beating-roll by ts revolution mixes thoroughly the pulp with the solutionsof chlorine or chloride of lime and the metallic oxides therein, when by the action of the heat large volumes of oxygen are produced within the mass of the pulp and in contact "with each fiber thereof, and as the oxygen is generated the bleaching is immediately efl'ected. After the bleaching 1s completed the whole mass of the wood-pulp is acidulated with dilute acid, decomposing the oxides, which are then washed out in combination with the acid, leaving the pulp clean and perfectly white. Y

Chlorine-gas or water saturated with chlo- I then fill the *rine, or any solution susceptible of yielding oxygen by the action bf the metallic oxides,

may be used and mixed, in the same manner. as hereinbefore described, with the pulp, water, and oxides in the bleaching-engine, and

treated in the same manner,,and when heated the same results will follow and alarge volume of oxygen will be generated, and when in con tact with various fibrous materials and the wood pulp bleaching it to apernianent white in a few minutes, 1

To accelerate the process of bleaching, more metallic oxide can be added at any time duringthe operation. M

It is a well-known fact that in the use of chlorine when it is heated it' leavesits solution and goes off into the air. In this process the oxygen is not formed and the. bleaching is not accomplished unless heat is applied and the chlorine or other solution or mixture containing oxygen brought into contact with the 'metallic oxide. The nearer to but under the boilingpoint this process is operated the more voluminous will be the generation of the oxygen; and the more efficient apd immediate will be itsbleaching properties.

I do not limit myself to the use of chlorine as the source of oxygen to be used in this bleaching process. 1- Any other source compatiof the unbleached material.

ble with the operation of bleaching and the material-to be bleached which will give up its oxygen-byt-he action of the metallic oxides may be used; but the oxygen must be gener- .ated in contact with the materalto be,bleached eitherin the air or in the bath. c .When the metallic-oxide bath is used in and preparatory'to, or as the first part of, the process of bleaching, it will completely protect the most delicate fibers of the material being bleached from the destructive action of the.

bleaching process; thoroughly preventing the weakening of the fibers by the chemical action, leaving the fibers intact with all the strength The metallic oxide bath is importantin this process in its twofold capacity, first, for protecting the fibers from decomposition and deterioration-by-thc chemical action during the process, and, sec- 0nd, as the source of the oxygen or the agency \through which it is developed fromsolutions and substances containing it. V 1 Having fully describedany invention, what I desire to claim, and secure by Letters Patent, 1s-

1. The process of bleaching wood pulp and other fibrous material by the generation of oxygen in contactwith it in a bath. of metallic oxides in water, substantially as described.

2. The processiof bleaching wood pulp andof the material and in contact with the points "of generation of the oxygen, substantially as described.

4. The process of bleaching wood pulp and anyother fibrous material within a metallic- .oxi eibath with chlorine added, whereby oxygen is generated and the bleaching effected while, the oxygen isbeing developed, as here in set forth.

5. The transformation of chlorine and water .orother solutions by metallic oxide into oxygen in a bath orin the air under heat in contact with Wood pulp or any other fibrous material producing oxygen, thereby bleaching the fibrous material, substantially as herein described. p

6. The decomposition of metallic oxides, producing oxygen, with chlorine or any other solutions containing oxygen in a bath or in the air under heat and in contact with wood pulp 'or any' other fibrous material generating large volumes of oxygen, thereby bleaching the fibers of the pulp, &c., substantially as herein set forth and described.

7 The formation of large volumes of oxygen by the agency and actionof chlorine or other substances with metallic oxides in a bath or in the air in contact with wood pulp or any other fibrous material-while under heat, thereby bleaching the material with the oxygen as it is developed in contact with the textile or fibrous material, as herein fully described and Ioo set forth.

- 8. In a process of bleaching, the use of a metallic-oxide bath for the protection and pros ervation of the fibers of the material from de-.

composition, preventing the strength of the fibers from being weakened while exposed for any length. of time to the action of the bleach- ,GOLDSBURY HARDEN roan).

Witnesses: EDMUND A. Monsn, EMMET T. JOHNSON. 

